Echoing the overall sentiments of the U.S. economy, U.S. retail sector sales fell (apparently) unexpectedly in January by the most since June 2012, as initial claims for jobless benefits rose more than forecast.

The United States Census Bureau announced that advance estimates of U.S. retail sector and food services sales for January decreased 0.4% month-over-month to $427.8 billion. In December, retail sector sales slipped 0.1% month-over-month to $429.5 billion. (Source: “Advance Monthly Sales for Retail and Food Services January 2014,” United States Census Bureau web site, February 13, 2014.)

Not surprisingly, analysts everywhere were blaming the cold weather for the weaker-than-expected results, noting that components that depend on foot traffic—including auto dealers, department stores, and restaurants—were hindered by the unusually cold weather. But on closer inspection, I think our energy would be better spent blaming the economy for the poor numbers rather than the weather.

For starters, the U.S. Census Bureau considers retail sector sales at 13 different kinds of businesses, including motor vehicle and parts dealers, furniture and home furnishing stores, electronics and appliance stores, food and beverage stores (which includes grocery store stocks), and clothing and clothing accessories stores. Of the 13 different sectors, nine reported month-over-month declines.

The biggest declines in the retail sector were from motor vehicle and parts dealers (-2.1%); sporting goods, hobby, book, and music stores (-1.5%); department stores (-1.5%); and clothing and clothing accessories stores (-0.9%). These four industries are more representative of discretionary spending than essential services, like food.

Having said that, at the other end of the spectrum, essential retail sector services, like food and beverage stores (which include grocery store stocks) and gas stations, experienced month-over-month increases.

If weather was to blame for weak retail sector sales in January, I would expect to see retail sector sales to be down in all areas that rely on foot traffic. But that’s not what we’re seeing. People are spending money at grocery store stocks (0.4%) and gas stations (1.1%). We’ve even increased our year-over-year spending on food services and drinking places (3.2%). Basically, when push comes to shove, we need to eat and get to work—which isn’t so dependent on the temperature outside.

This means that Americans are willing to face the cold weather for what they need, but not for what they’d like. This is more reflective of a general malaise regarding the economy than the weather. After all, if you have the money and need a car or TV, you’ll get one.

For investors, this might mean avoiding retail sector stocks that rely heavily on discretionary spending. As long as the U.S. economy faces economic headwinds, it might be a good idea to consider non-discretionary retail sector stocks.

One area of the retail sector that has been experiencing solid growth is grocery store stocks. According to the most recent data from the U.S. Department of Agriculture (USDA), sales by the 20 largest grocery store stocks food retailers totaled $420.8 billion in 2012 and accounted for 62.1% of all U.S. grocery store stocks’ sales—a 39.2% increase from 1992.

The Kroger Co. (NYSE: KR), one of the largest traditional grocery store stocks, reported strong third-quarter results and is up more than 43% year-over-year. Another one of the stronger grocery store stocks, SUPERVALU INC. (NYSE: SVU) is up 140% since the beginning of 2013, while another one of these grocery store stocks, Safeway Inc. (NYSE: SWY), says it is in advanced talks with Cerberus Capital Management, L.P. over a leveraged buyout. A deal with Cerberus would unite Safeway with the firm’s “Albertson’s” grocery store stocks chain.